Hosomi-Sakurai Reaction

The Hosomi Sakurai Reaction involves the Lewis acid-promoted allylation of various
electrophiles with allyltrimethysilane. Activation by Lewis acids is
critical for an efficient allylation to take place.

Mechanism of the Hosomi-Sakurai Reaction

Note: Silicon stabilizes β carbocations (β effect)

Only catalytic amounts of Lewis acid are needed in some newer protocols. Note
the use of allylsilyl chlorides instead of allyltrimethylsilane: